Scalable integrated logic and non-volatile memory

ABSTRACT

A scalable, logic transistor has a pair of doped regions for the drain and source. A gate insulator layer is formed over the substrate and between the drain and source regions. A gate stack is formed of a gate layer, such as polysilicon or metal, between two metal nitride layers. A compatible non-volatile memory transistor can be formed from this basic structure by adding a high-K dielectric constant film with an embedded metal nano-dot layer between the tunnel insulator and the gate stack.

RELATED APPLICATION

This Application is a Continuation of U.S. application Ser. No.10/995,839 titled “Scalable Integrated Logic and Non-Volatile Memory,”filed Nov. 23, 2004, (Allowed) which is commonly assigned andincorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to memory and logic devices andin particular the present invention relates to scalable non-volatilememory devices in logic technology environment.

BACKGROUND OF THE INVENTION

Memory and logic devices are typically provided as internal,semiconductor, integrated circuits in computers and many otherelectronic devices including handheld devices such as cellulartelephones and personal digital assistants. There are many differenttypes of memory including static random-access memory (SRAM), read onlymemory (ROM), flash memory, dynamic random access memory (DRAM), andsynchronous dynamic random access memory (SDRAM) that are functionallyintegrated with logic devices such as microprocessors, microcontrollers,digital signal processors, programmable logic devices, wirelesscommunication, and networking.

Many current and future devices require increasing integration of logicand memory functions within the same integrated circuit technology.Current microprocessors, for example, embed ROM and SRAM arrays withlogic libraries, logic device (e.g., ALU), and logic circuits to achievedesired device functionality within the same chip. A basic buildingblock for a logic cell is a CMOS inverter that consists of a pair ofPMOS and NMOS transistors integrated to have common input and outputnodes between power supply (V_(DD)) and ground potentials. As the sizeof a unit transistor shrinks with scaling, large arrays of memoriesincluding DRAMs are being integrated into logic devices to achievepowerful functions.

Conventional DRAM cells are comprised of a switching transistor and anintegrated storage capacitor tied to the storage node of the transistor.Charge storage is enhanced by providing appropriate storage capacity inthe form of a stacked capacitor or a trench capacitor in parallel withthe depletion capacitance of the floating storage node. DRAM cells arevolatile and therefore lose data when the power is removed.Additionally, due to leakage, the capacitor must be refreshedperiodically to maintain the charge.

As computers and other devices mentioned above become smaller and theirperformance increases, the computer memories have also gone through acorresponding size reduction and performance increase. For example, DRAMcells, typically comprised of silicon IC technology, has beenprogressively scaled in feature size from the nearly 2000 nm nodetechnology of prior years to the current 100 nm node technology.

During this period, power supply voltages have been scaled from nearly 8volts to the approximately 2 volts that is presently used. The gateinsulator, primarily SiO₂, has had an effective oxide thickness (EOT)that has been scaled from 50 nm to approximately 5 nm at the presenttime. At thicknesses below 5 nm, leakage through the oxide becomesappreciable thus providing constraints and challenges towards furtherscalability from the standpoint of power, speed, and circuitreliability. This is especially true for dynamic circuits.

Aside from oxide integrity and reliability, transistor design for deepsub-micron channel length (i.e., L <200 nm) requires critical control ofthermal budget to achieve control of short channel effect, performance,and reliability. Integration of embedded DRAM below 100 nm node has beena challenge not only due to capacitor scalability concerns of DRAM cellsbut also because of the requirement for higher thermal budgets toachieve leakage, yield, and density objectives of the embedded DRAMcells.

Recently, embedded non-volatile memory (NVM) technology has been gainingconsiderable attention due to the potential of low power and hand-helddevice applications. It would be desirable to have the non-volatileflash memory attributes in a cell that has DRAM performance. However,conventional floating gate flash memory technology has not been scalablein power supply voltage levels, consumes higher than desired powerduring programming, and also requires high programming voltages (e.g.,10-20V for the 100 nm technology node). Embedding such a device requireson-chip generation of the high voltages and routing these voltages in anotherwise scaled low voltage logic technology adds considerable processcomplexity and cost and compromises functionality.

For the reasons stated above, and for other reasons stated below whichwill become apparent to those skilled in the art upon reading andunderstanding the present specification, there is a need in the art fora more scalable, low power, high performance integrated logic memorythat would provide high performance logic and non-volatile memory atlower power.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross-sectional view of one embodiment of a logic fieldeffect transistor element in accordance with the structure and method ofthe present invention.

FIG. 2 shows a cross-sectional view of one embodiment of a flashtransistor element in accordance with the structure and method of thepresent invention.

FIG. 3 shows a cross-sectional view of one embodiment of a single gateNOR flash cell in accordance with the structure and method of thepresent invention.

FIG. 4 shows a cross-sectional view of one embodiment of a split gateNAND flash cell in accordance with the structure and method of thepresent invention.

FIG. 5 shows a block diagram of one embodiment of an electronic systemof the present invention.

DETAILED DESCRIPTION

In the following detailed description of the invention, reference ismade to the accompanying drawings that form a part hereof and in whichis shown, by way of illustration, specific embodiments in which theinvention may be practiced. In the drawings, like numerals describesubstantially similar components throughout the several views. Theseembodiments are described in sufficient detail to enable those skilledin the art to practice the invention. Other embodiments may be utilizedand structural, logical, and electrical changes may be made withoutdeparting from the scope of the present invention. The followingdetailed description is, therefore, not to be taken in a limiting sense,and the scope of the present invention is defined only by the appendedclaims and equivalents thereof. The terms wafer or substrate used in thefollowing description include any base semiconductor structure. Both areto be understood as including silicon-on-sapphire (SOS) technology,silicon-on-insulator (SOI) technology, thin film transistor (TFT)technology, doped and undoped semiconductors, epitaxial layers of asilicon supported by a base semiconductor structure, as well as othersemiconductor structures well known to one skilled in the art.Furthermore, when reference is made to a wafer or substrate in thefollowing description, previous process steps may have been utilized toform regions/junctions in the base semiconductor structure, and termswafer or substrate include the underlying layers containing suchregions/junctions.

The thermal budget of an integrated circuit includes all of the hightemperature steps required for junction formation and activation as wellas thin film formation (deposition/oxidation) and annealing to reducestress and defects. The thermal processes used to manufacture integratedcircuits help define region, film, and layer interfaces. These processessupply the thermal energy required for oxidation, film formation, dopantactivation, and defect control. Thermal budget control is important todevice and junction performance since the thermal processes can alsodrive diffusion and defect annealing.

The structure and method of the present invention employs low thermalbudget integration for both the logic transistors and the non-volatilememory transistors. This process scheme and the materials used for thelogic and non-volatile memory transistor architecture provide greaterscalability and compatibility in operating voltages.

FIG. 1 illustrates a cross-sectional view of one embodiment of a logicfield effect transistor (FET) incorporating the low thermal budgetstructure and method of the present invention. The FET is comprised of asubstrate 100 with two doped regions 101 and 103 that act as the sourceand drain regions. The doped regions 101 and 103 are separated fromother transistors by shallow trench isolation (STI) 120 and 121.Metal-silicide contacts 105 and 107 are formed on the doped regions 101and 103 respectively.

In one embodiment, the doped regions 101 and 103 are n+ regions dopedinto a p-type substrate 100 to form an NFET transistor element. Thesediffusion regions can be formed using n+ doped amorphous silicon,followed by rapid thermal anneal to limit thermal budget and subsequentsilicidation. Similarly, for a PFET transistor element (not show), p+diffusion source/drain regions could be formed over an n-well region.The source/drain regions and substrate of the present invention are notlimited to any one conductivity type or formation technique.

A gate oxide insulator 109 for the logic FET is formed over thesubstrate and substantially between the source/drain regions 101 and103. The gate insulator 109 is comprised of an ultra-thin silicondioxide (SiO₂), silicon nitride (SiN), or silicon oxynitride (SiON)layer with a relative dielectric constant (K) in the range of 5.0-7.5.The SiON layer has the added benefit of low leakage for longer chargeretention. Other possibilities include a combination of one or moremonolayers of SiO₂ followed by an ultra-thin layer of high-k laminatesuch as Pr₂O₃ or PrSiON. This limits the gate insulation leakage currentto the desired level.

The gate insulator 109 can be formed on the substrate 100 by atomiclayer deposition (ALD). In one embodiment, the gate insulator 109 canhave a total physical thickness in the range of 2-2.5 nm for a powersupply voltage of V_(DD)=1.0V. This thickness can be appropriatelyscaled for lower power supply voltage generation. This provides anequivalent oxide thickness (EOT) of 1.0-1.5 nm.

An ultra-thin layer (e.g., 1-2 nm) of conductive metal nitride 111 isformed over the gate oxide insulator 109. This layer 111 can be tantalumnitride (TaN), titanium nitride (TiN) or some other metal nitridematerial. This layer 111 acts as an appropriate passivation layer anddiffusion barrier for undesirable impurities and dopants.

A gate layer 113 is then formed over the passivation layer 111. The gatelayer 113 can be comprised of a doped polysilicon or metal material. Inone embodiment, the polysilicon 113 is an n+ conductivity material thatis formed by using phosphorus doped amorphous silicon followed by RTAanneal and silicidation (e.g., nickel silicidation for both gate anddiffusion). In an alternate embodiment, plasma chemical vapor deposition(CVD) or some other low temperature processing of boro-silicate glass(for boron impurity) and phoso-silicate glass (for phosphorous impurity)might be employed for dopant sources.

In a silicon gate, a final RTA anneal step can be employed for dopantactivation, interface state density control, leakage control, and filmstability for the gate stack. A top layer 115 of metal silicide, such asnickel silicide, is formed over the silicon gate 113.

For metal gate processing, an appropriate ALD process can be employed.In one embodiment, this processing can include a layer 115 of ALDTungsten or Nickel combined with tungsten-silicide or nickel-siliciderespectively.

The fixed threshold FET of the present invention is designed to have athreshold V_(t) in the range of 0.3-0.4 V. For V_(dd)=1V, L=0.05 μm,W=1.0 μm, I_(on) and I_(off) are expected to be >300 μA/μm and <1×10⁻⁹A/μm respectively. The gate leakage current is estimated to be <<1 A/cm²at V_(dd). The interface state density is expected to be <1×10¹¹/cm².

FIG. 2 illustrates a cross-sectional view of one embodiment of anon-volatile memory device that incorporates the low thermal budgetstructure and method of the present invention. The non-volatile memorydevice shares many of the same components of the logic FET illustratedin FIG. 1.

A tunnel oxide insulator 209 for the memory transistor is formed overthe substrate and substantially between the source/drain regions 201 and203. The tunnel insulator 209 is comprised of an ultra-thin silicondioxide (SiO₂), silicon nitride (SiN) or silicon oxynitride (SiON) layerwith a relative dielectric constant (K) in the range of 5.0-7.5. TheSiON layer has the added benefit of longer charge retention. Otherpossibilities include a combination of one or more monolayers of SiO₂followed by an ultra-thin layer of high-k laminate such as praseodymiumoxide (Pr₂O₃) or praseodymium silicon oxynitride (PrSiON). This limitsthe gate insulation leakage current to the desired level.

The tunnel insulator 209 can be formed on the substrate 200 by atomiclayer deposition (ALD). In one embodiment, the tunnel insulator 209 canhave a total physical thickness in the range of 2-2.5 nm for a powersupply voltage of V_(DD)=1.0V. This thickness can be appropriatelyscaled for lower power supply voltage generation. This provides anequivalent oxide thickness (EOT) of 1.0-1.5 nm.

The memory transistor's gate stack 202 is comprised of a lowerultra-thin layer (e.g., 1-2 nm) of conductive metal nitride 211. Thislayer 211 can be tantalum nitride (TaN), titanium nitride (TiN) or someother metal nitride material. This layer 211 acts as an appropriatepassivation layer and diffusion barrier for undesirable impurities anddopants.

A gate layer 213 is formed over the passivation layer 211. The gatelayer 213 can be comprised of a doped polysilicon or metal material. Inone embodiment, the polysilicon 213 is an n+ conductivity material thatis formed by using phosphorus doped amorphous silicon followed by RTAanneal and silicidation (e.g., nickel silicidation for both gate anddiffusion). In an alternate embodiment, plasma chemical vapor deposition(CVD) or some other low temperature processing of boro-silicate glass(for boron impurity) and phoso-silicate glass (for phosphorous impurity)might be employed for dopant sources.

In a silicon gate, a final RTA anneal step can be employed for dopantactivation, interface state density control, leakage control, and filmstability for the gate stack. A top layer 215 of metal silicide, such asnickel silicide, is formed over the silicon gate 213.

For metal gate processing, an appropriate ALD process can be employed.In one embodiment, this processing can include a layer 215 of ALDTungsten or Nickel combined with tungsten-silicide or nickel-siliciderespectively.

In one embodiment, the gates for both the logic FET element and thenon-volatile memory element are substantially identical. Alternateembodiments might make slight changes such as material differences.

The gate stack 202 is formed over a layer 210 comprised of extremelyhigh density metal nano-dots embedded into a high dielectric constant(high-K) insulator material. The embedded metal nano-dots are used as acharge retention layer for the non-volatile memory transistor. Eachmetal dot acts as an isolated, one-dimensional, small floating gate.Therefore, even if a charge leakage path exists between one smallfloating gate and the substrate or the control gate, the remainingnano-dots in the film layer retain the charge.

In one embodiment, the density range of the metal nano-dots in thehigh-K insulator layer 210 is in the range of 1×10¹³ to 10×10¹³ withtypical dot sizes in the range of 1-3 nm and spaced greater than 3 nmapart in the high-K dielectric material. Alternate embodiments can usedifferent densities, dot sizes, and spacing.

The metal dot elements can include platinum (Pt), gold (Au), Cobalt(Co), Tungsten (W) or some other metal that provides deep energyelectron and hole traps. In one embodiment, the metal dot layer 210 isdeposited by sputtering or evaporation at relatively low temperatures.

The metal dots are embedded in a high-K dielectric medium 210 that couldalso be co-sputtered or deposited subsequently by an ALD technique. Thehigh-K dielectric film 210 might be comprised of Alumina (Al₂O₃),Hafnium (HfO₂), Tantalum Oxide (Ta₂O₅), HfTaO, HfAlO, ZrO₂, LaSiON, orlaminated combinations of the above that are deposited by an ALDtechnique or sputtering. The high-K dielectric medium 210 can further becomprised of Zirconium Oxide (ZrO₂), Lanthanum Oxide (La₂O₃),Praseodymium Oxide (Pr₂O₃), and high-K oxynitrides such as HfSiON,PrSiON, and mixed high-K oxides of Al and La, Al and Pr, Al and Zr, andsilicides.

A typical thickness for the dielectric film 210 may range from 5-10 nmwith an EOT ranging from 2-3 nm. The overall EOT for the non-volatileFET gate insulator stack may be of 3.5-4 nm for a programming voltage of2-4 Volts to produce a sub-microsecond programming time. Alternateembodiments can use different thickness ranges to provide differentprogramming voltages.

The non-volatile transistor of FIG. 2 could be programmed at controlgate voltage of ±2V to ±4V for 10-1000 ns with V_(t(hi))=1.6V andV_(t(low)=)0.2V. The device could be read at 0.7V (i.e.,V_(dd)−V_(tfixed)). The device would exhibit retention of 10⁶ secondsand an endurance of 10¹⁴ cycles. The programming voltage could beachieved by simple boot strapped circuitry on-chip and could be appliedto the control gate for V_(t(hi)) for electron trapping and to thesubstrate for V_(t(low)) for electron detrapping and hole trapping.

The method to manufacture the above-described transistors of the presentinvention uses standard silicon gate process technology but alsoincludes multiple ALD steps to provide low temperature processing ofhighly controllable ultra-thin films. These steps could include a highpressure, low temperature forming gas anneal or RTA after the nitride oroxynitride gate insulator processing to reduce interface state densityat the Si/insulator interface. The low temperature anneal alsostabilizes Si—H bonds at the interface. Additionally, the thermal budgetfor impurity doping and activation is controlled by using dopedamorphous silicon or doped glass as impurity sources and RTA as statedearlier.

During the gate stack process integration, an oxide (e.g., SiO₂) hardmask is used over the logic transistor elements to protect the tunnelinsulator during the processing of the metal nano-dots and high-Kinsulator deposition steps for the non-volatile device. The oxide isselectively etched off and the common gate metal deposition steps aresubsequently performed for both logic and non-volatile transistorelements.

The flash memory and logic transistors of the present invention can beused in both NOR architecture (including NROM) and NAND architecturememory arrays. The flash memory cells can be used to store data in anon-volatile fashion while the logic FETs can be used for control/accesspurposes in the memory array and to provide a variety of logicfunctions.

In a NOR configuration, the memory cells are arranged in a matrix andoperate in parallel mode. The gates of each metal nano-dot memory cellof the array matrix are connected by rows to wordlines and their drainsare connected to column bitlines. The source of each metal nano-dotmemory cell is typically connected to a common source line.

A NAND flash memory device is comprised of an array of metal nano-dotcells arranged in series chains in a string. Each of the metal nano-dotcells are coupled drain to source in each series chain. A word line thatspans across multiple series chains is coupled to the control gates ofeach floating gate cell in a row in order to control their operation.The bitlines are eventually coupled to sense amplifiers that detect thestate of each cell.

FIG. 3 illustrates a cross-sectional view of one embodiment of singlegate NOR flash memory cells in accordance with the present invention.The substrate 300, in the illustrated embodiment, is a p-type siliconwith n+ doped areas 301-303 that act as the source/drain regions for thecells. Alternate embodiments use different conductivity materials forthe substrate/doped areas.

The doped area that acts as the drain region 301 is coupled to a firstbitline ‘A’ 305 through a metallized contact. The doped area that actsas the common source region 302 is also coupled through anothermetallized contact elsewhere (not shown) in the cross-section. The dopedregion 303 for the neighboring bit is coupled to a second bitline 306‘B’ through a metallized contact as shown in FIG. 3.

FIG. 4 illustrates a cross-sectional view of one embodiment ofsplit-gate NAND flash memory cells in accordance with the presentinvention. This figure illustrates only a small portion of a serialstring of elements. A typical memory string is comprised of 32 bits in astring. One bit is comprised of a non-volatile memory element and alogic element together (e.g., 401 and 410) as shown in the illustration.Other configurations may be comprised of only a non-volatile element asa single bit in a string.

Each logic element 410-412 in the NAND string comprises multiplefunctions. One function is to select a particular non-volatile memoryelement. A second function involves protection from over-erasure forthat particular non-volatile memory element.

The p-type substrate 400 is comprised of n+ doped regions 420 and 421that act as the source/drain regions. In this embodiment, the firstregion 420 is the drain region and the second region 421 is the sourceregion. Alternate embodiments can use different conductivity materialsfor the substrate/doped areas. Bitlines 425 and 426 are coupled to thesource/drain regions 420 and 421 through metallization contacts.

The array is comprised of a plurality of control/access transistors401-403 that function to control access to one of a plurality of memorycells 410-412. The non-volatile memory elements are comprised asdiscussed previously with the same composition as the logic transistorsexcept for the metal nano-dot layer embedded in the high-K dielectricmaterial.

FIG. 5 illustrates a functional block diagram of a memory device 500that can incorporate the memory cell structure of the present invention.The memory device 500 is coupled to a processor 510. The processor 510may be a microprocessor or some other type of controlling circuitry. Thememory device 500 and the processor 510 form part of an electronicsystem 520 that may also be a system on chip application. The memorydevice 500 has been simplified to focus on features of the memory thatare helpful in understanding the present invention.

The memory device includes an array of memory cells 530 that can becomprised of the logic and flash memory cells previously illustrated.The memory array 530 is arranged in banks of rows and columns. The gatesof each row of memory cells are coupled with a wordline while the drainand source connections of the memory cells are coupled to bitlines.

An address buffer circuit 540 is provided to latch address signalsprovided on address input connections A0-Ax 542. Address signals arereceived and decoded by a row decoder 544 and a column decoder 546 toaccess the memory array 530. It will be appreciated by those skilled inthe art, with the benefit of the present description, that the number ofaddress input connections depends on the density and architecture of thememory array 530. That is, the number of addresses increases with bothincreased memory cell counts and increased bank and block counts.

The memory device 500 reads data in the memory array 530 by sensingvoltage or current changes in the memory array columns usingsense/buffer circuitry 550. The sense/buffer circuitry, in oneembodiment, is coupled to read and latch a row of data from the memoryarray 530. Data input and output buffer circuitry 560 is included forbi-directional data communication over a plurality of data connections562 with the controller 510. Write circuitry 555 is provided to writedata to the memory array.

Control circuitry 570 decodes signals provided on control connections572 from the processor 510. These signals are used to control theoperations on the memory array 530, including data read, data write(program), and erase operations. The control circuitry 570 may be astate machine, a sequencer, or some other type of controller.

The memory device illustrated in FIG. 5 has been simplified tofacilitate a basic understanding of the features of the memory. A moredetailed understanding of internal circuitry and functions of memoriesare known to those skilled in the art.

Conclusion

In summary, the embodiments of the present invention provide a lowthermal budget (e.g., approximately less than 600° C.) integrationscheme to manufacture both logic and non-volatile memory transistorswith minimum added process complexity. Using low temperature techniquesand predetermined materials, transistors can be produced that have acompatible gate stack. Additionally, the transistors are scalable inoperating voltages such that special and complex process technology(e.g., well and isolation) as well as circuitry (e.g., charge pump andhigh voltage decoding) are not required for embedded logic and memoryoperation in a system on chip application.

Although specific embodiments have been illustrated and describedherein, it will be appreciated by those of ordinary skill in the artthat any arrangement that is calculated to achieve the same purpose maybe substituted for the specific embodiments shown. Many adaptations ofthe invention will be apparent to those of ordinary skill in the art.Accordingly, this application is intended to cover any adaptations orvariations of the invention. It is manifestly intended that thisinvention be limited only by the following claims and equivalentsthereof.

1. A non-volatile transistor comprising: a substrate comprising a pairof source/drain areas; a gate insulator formed on the substrate andsubstantially between the pair of source/drain areas; a charge retentioninsulator having embedded metal nano-dots formed over the gateinsulator; and a gate stack formed over the charge retention insulatorand comprising: a metal nitride layer formed over the gate insulator; agate layer formed over the metal nitride layer; and a metal silicidelayer formed over the gate layer.
 2. The transistor of claim 1 whereinthe substrate is a p-type silicon and the doped regions are n+ regions.3. The transistor of claim 1 wherein the gate layer is a polysilicongate.
 4. The transistor of claim 1 wherein the gate insulator is anoxide.
 5. A non-volatile memory transistor comprising: a substratecomprising a pair of source/drain areas; a tunnel insulator formed onthe substrate and substantially between the pair of source/drain areas;a charge retention layer with an embedded metal nano-dot layer formedover the tunnel insulator; a metal nitride layer formed over the chargeretention layer; a gate layer formed over the metal nitride layer; and ametal silicide layer formed over the gate layer.
 6. The transistor ofclaim 5 wherein the metal nano-dot layer is embedded in the chargeretention layer substantially closer to the tunnel insulator than themetal nitride layer.
 7. The transistor of claim 5 wherein the tunnelinsulator, charge retention layer, gate layer, the metal nitride layer,and the metal silicide layer are formed by low temperature processing.8. The transistor of claim 5 wherein a physical thickness of the tunnelinsulator is in a range of 2-2.5 nm and an effective oxide thickness ofthe tunnel insulator is in a range of 1-1.5 nm.
 9. A memory arraycomprising: a plurality of logic transistors, each transistorcomprising: a substrate comprising a pair of source/drain regions; agate insulator formed over the substrate and substantially between theplurality of doped regions; and a first gate stack formed over the gateinsulator and comprising a metal nitride layer formed over the gateinsulator; a gate layer formed over the metal nitride layer; and a metalsilicide layer formed over the gate layer; and a plurality ofnon-volatile memory transistors, each non-volatile memory transistorcoupled to at least one of the logic transistors, each non-volatilememory transistor comprising: a substrate comprising a pair ofsource/drain regions; a tunnel insulator formed over the substrate andsubstantially between the plurality of doped regions; a charge retentionlayer with an embedded metal nano-dot layer formed over the tunnelinsulator; and a second gate stack, having the same architecture as thefirst gate stack, formed over the charge retention layer.
 10. The arrayof claim 9 wherein the first and second gate stacks are comprised of atantalum nitride layer, a polysilicon gate material, and a tungstensilicide layer.
 11. The array of claim 9 wherein the first and secondgate stacks are comprised of a titanium nitride layer, a polysilicongate material, and a nickel silicide layer.
 12. A non-volatile memorytransistor comprising: a substrate comprising a pair of source/drainareas; a tunnel insulator formed on the substrate and substantiallybetween the pair of source/drain areas; a dielectric layer with anembedded metal nano-dot layer formed over the tunnel insulator; atitanium nitride layer formed over the dielectric layer; a metal gatelayer formed over the titanium nitride layer; and a metal silicide layerformed over the gate layer, wherein the metal silicide is comprised ofone of cobalt, nickel, tungsten, or titanium.
 13. The transistor ofclaim 12 wherein the titanium nitride layer is a passivation layer anddiffusion barrier.
 14. The transistor of claim 12 wherein the tunnelinsulator is comprised of a plurality of monolayers of SiO₂.
 15. Thetransistor of claim 14 and further including a laminate layer of one ofPr₂O₃ or PrSiON.
 16. A non-volatile memory transistor comprising: asubstrate comprising a pair of source/drain areas; a tunnel insulatorformed on the substrate and substantially between the pair ofsource/drain areas; a dielectric layer with an embedded metal nano-dotlayer formed over the tunnel insulator; a tantalum nitride layer formedover the dielectric layer; a metal gate layer formed over the tantalumnitride layer; and a metal silicide layer formed over the gate layer,wherein the metal silicide is comprised of one of cobalt, nickel,tungsten, or titanium.
 17. A non-volatile memory transistor comprising:a substrate comprising a pair of source/drain areas; a tunnel insulatorformed on the substrate and substantially between the pair ofsource/drain areas; a dielectric layer with an embedded metal nano-dotlayer formed over the tunnel insulator wherein the dielectric layer iscomprised of one of Al₂O₃, HfO₂, ZrO₂, Ta₂O₅, HfSiON, HfTaO, Pr₂O₃,PrSiON, LaSiON, HfAlO, or mixed oxides of Al and La, Al and Pr, and Aland Zr; a titanium nitride layer formed over the dielectric layer; ametal gate layer formed over the titanium nitride layer; and a metalsilicide layer formed over the gate layer, wherein the metal silicide iscomprised of one of cobalt, nickel, tungsten, or titanium.
 18. Anon-volatile memory transistor comprising: a substrate comprising a pairof source/drain areas; a tunnel insulator formed on the substrate andsubstantially between the pair of source/drain areas; a dielectric layerwith an embedded metal nano-dot layer formed over the tunnel insulatorwherein the dielectric layer is comprised of one of Al₂O₃, HfO₂, ZrO₂,Ta₂O₅, HfSiON, HfTaO, Pr₂O₃, PrSiON, LaSiON, HfAlO, or mixed oxides ofAl and La, Al and Pr, and Al and Zr; a tantalum nitride layer formedover the dielectric layer; a metal gate layer formed over the tantalumnitride layer; and a metal silicide layer formed over the gate layer,wherein the metal silicide is comprised of one of cobalt, nickel,tungsten, or titanium.
 19. A non-volatile memory transistor comprising:a substrate comprising a pair of source/drain areas; a tunnel insulatorformed on the substrate and substantially between the pair ofsource/drain areas; a dielectric layer with an embedded metal nano-dotlayer, comprising a plurality of metal nano-dots, formed over the tunnelinsulator wherein the plurality of metal nano-dots are comprised of oneof platinum, gold, cobalt, or tungsten; a metal nitride layer formedover the dielectric layer wherein the metal nitride is one of tantalumnitride or titanium nitride; a metal gate layer formed over the metalnitride layer; and a metal silicide layer formed over the gate layer,wherein the metal silicide is comprised of one of cobalt, nickel,tungsten, or titanium.